1. Technical Field
The present invention relates to a method for producing metal nanoparticles and metal nanoparticles produced thereby, in particular, a method for metal nanoparticles including 2 kinds of dispersants on their surface and metal nanoparticles produced thereby.
2. Description of the Related Art
Noncontact direct writing technology using inkjet method has advantage not only in the cost for materials but also the manufacturing time, since it allows precise ejection to desired positions with fixed quantity. Since for the industrial applications, ink suitable for the inkjet method should be developed, many researches about methods for producing metal particles in mass production with low cost have been performed in order to develop materials for the inkjet method.
Though the vapor-phase method for particle production is advantageous to produce nanoparticles, but it has problems of complicated processes, difficulty in manufacturing with uniform quality and setting up a safe working environment because of high risk of environmental pollution and dangerous explosion during the process.
On the other hand, the solution method has advantage in that it has high yield rate particularly in the precious metals, but capping the surface of particles with various kinds of dispersants is required to lower the curing temperature of ink. Japan patent application No. JP2005-81501 discloses metal nanoparticles and manufacturing method of the nanoparticles around which organic metal compounds and/or amine metal complexes are attached, but the method has quite low yield rate and is not appropriate for manufacturing low price materials.
Therefore, a new method that allows mass production of metal nanoparticles whose surface capped with appropriate dispersants in order to cure ink at low temperature is needed.